Question

The local hormone secreted by atrial wall of heart is known as
A. Secretin
B. Gastrin
C. ANF
D. None of the above

Answer 1

Hint: Heart is the muscular organs size of the heart is like fist and present behind and left side of the breastbone. The main function of the heart is pumping the blood with the help of arteries and veins which is known as the cardiovascular system.

Complete Answer:
- The human heart has four chambers: right and left atrium and right and left ventricle.
- The coronary arteries are present on the surface of the heart and deliver the oxygen- rich blood to the heart muscle.
- Atrial natriuretic peptide (ANP) also called as atrial natriuretic factor (ANF) is a natriuretic peptide hormone which is released by the cardiac atria that in humans is encoded by the NPPA gene.
- Natriuretic peptides are ANP, BNP, and CNP. This peptide belongs to the family of hormone/paracrine factors which are structurally related to each other.
- The primary work of ANP is doing the reduction in extracellular fluid (ECF) volume by increasing the amount of renal sodium excretion.
- ANP is synthesized and secreted by cardiac muscle cells in the walls of the atria in the heart. - These cardiac muscle cells have volume receptors which work to increase stretching of the atrial wall by increasing the blood volume.

So the correct answer is ANP ( Atrial natriuretic peptide).

Note: Chemically ANP is a 28-amino acid peptide and 17-amino acid ring. The ring formation by disulfide bond between two cysteine residues at positions 7 and 23.